Substrate processing apparatus for maintaining a more uniform temperature during substrate processing

Abstract

A substrate processing apparatus that includes a process tank having a pair of opposed sidewalls for storing a chemical liquid, and processing a plurality of substrates by the chemical liquid; a substrate holding mechanism including a holding part for holding the plurality of substrates, and a back part connected to the holding part and interposed between the substrates held by the holding part and one sidewall of the pair of opposed sidewalls when the substrate holding mechanism is loaded into the process tank. A heating device is disposed on the process tank for heating the stored chemical liquid. The heating device includes at least a first heater disposed on the one sidewall, and a second heater disposed on the other sidewall of the pair of opposed sidewalls. Energy outputs of the first heater and the second heater are independently controlled.

The invention claimed is: 
     
       1. A substrate processing apparatus comprising:
 a process tank including a pair of opposed sidewalls, the process tank being configured to store a chemical liquid therein and to process a plurality of substrates by the chemical liquid; 
 a substrate holding mechanism including a holding part configured to hold the plurality of substrates vertically, and a back part connected to the holding part, the back part being interposed between the substrates held by the holding part and one sidewall of the pair of opposed sidewalls of the process tank when the substrate holding mechanism is loaded into the process tank, the substrate holding mechanism being configured to immerse the substrates held by the holding part into the chemical liquid; and 
 a heating device disposed on the process tank, the heating device being configured to heat the stored chemical liquid; 
 wherein 
 the heating device includes a first heating device disposed on the one sidewall of the process tank, and a second heating device disposed on the other sidewall thereof, 
 a control unit is connected to the first heating device and the second heating device, 
 the control unit is configured to independently control an energy output of the first heating device and an energy output of the second heating device, the control unit is configured to control the first heating device and the second heating device by varying values of currents provided to the first heating device and the second heating device such that the energy output of the first heating device is larger than the energy output of the second heating device, so as to heat the chemical liquid stored in the process tank, and 
 when the substrate holding mechanism is loaded into the process tank, the back part is interposed between the substrates held by the holding part and the first heating device. 
 
     
     
       2. The substrate processing apparatus according to  claim 1 , wherein:
 the process tank further includes two other sidewalls and a bottom part; 
 third heating devices are disposed respectively on the two other sidewalls and the bottom part of the process tank; and 
 the control unit is configured to control the first heating device and the second heating device such that the energy output of the first heating device and the energy output of the second heating device are respectively maintained constant, and to control the third heating devices such that a temperature of the chemical liquid stored in the process tank becomes a desired temperature. 
 
     
     
       3. The substrate processing apparatus according to  claim 2 , wherein
 a temperature detecting device configured to detect the temperature of the stored chemical liquid is disposed in the process tank, and 
 the control unit is configured to control the third heating devices based on the temperature detected by the temperature detecting device. 
 
     
     
       4. The substrate processing apparatus according to  claim 2 , wherein the control unit is configured to control the first heating device and the third heating devices such that energy outputs of the third heating devices are substantially the same as the energy output of the first heating device. 
     
     
       5. The substrate processing apparatus according to  claim 2 , wherein the control unit is configured to control the first heating device and the third heating devices such that energy outputs of the third heating devices are larger than the energy output of the first heating device. 
     
     
       6. The substrate processing apparatus according to  claim 1 , wherein:
 the process tank further includes two other sidewalls and a bottom part; 
 third heating devices are disposed respectively on the two other sidewalls and the bottom part of the process tank; and 
 the control unit is configured to control the third heating devices such that energy outputs of the third heating devices are maintained constant and to control the first heating device and the second heating device such that a temperature of the chemical liquid stored in the process tank becomes a desired temperature. 
 
     
     
       7. The substrate processing apparatus according to  claim 6 , wherein
 a temperature detecting device configured to detect the temperature of the stored chemical liquid is disposed in the process tank, and 
 the control unit is configured to control the first heating device and the second heating device based on the temperature detected by the temperature detecting device. 
 
     
     
       8. The substrate processing apparatus according to  claim 6 , wherein the control unit is configured to control the first heating device and the third heating devices such that the energy outputs of the third heating devices are substantially the same as the energy output of the first heating device. 
     
     
       9. The substrate processing apparatus according to  claim 6 , wherein the control unit is configured to control the first heating device and the third heating devices such that the energy outputs of the third heating devices are larger than the energy output of the first heating device. 
     
     
       10. A substrate processing apparatus comprising:
 a process tank including a pair of opposed sidewalls, the process tank being configured to store a chemical liquid therein and to process a plurality of substrates by the chemical liquid; 
 a substrate holding mechanism including a holding part configured to hold the plurality of substrates vertically, and a back part connected to the holding part, the back part being interposed between the substrates held by the holding part and one sidewall of the pair of opposed sidewalls of the process tank when the substrate holding mechanism is loaded into the process tank, the substrate holding mechanism being configured to immerse the substrates held by the holding part into the chemical liquid; and 
 a heating device disposed on the process tank, the heating device being configured to heat the stored chemical liquid; 
 a chemical-liquid supply part disposed in the process tank, the chemical-liquid supply part being configured to supply the chemical liquid to the substrates immersed in the chemical liquid, 
 wherein 
 the heating device includes a first heating device disposed on the one sidewall of the pair of opposed sidewalls of the process tank, and a second heating device disposed on the other sidewall thereof, 
 a control unit is connected to the first heating device and the second heating device, 
 the control unit is configured to independently control an energy output of the first heating device and an energy output of the second heating device by varying values of currents provided to the first heating device and the second heating device; 
 a plurality of holding grooves capable of being engaged with the substrates are formed in the holding part of the substrate holding mechanisms, and 
 the chemical-liquid supply part includes: a plurality of substrate position supply holes arranged so as to correspond to gaps between the holding grooves, the substrate position supply holes being configured to supply the chemical liquid to the gaps between the substrates; and a back-part side supply hole arranged so as to correspond to a gap between the holding groove, which is formed closest to the back part among the plurality of holding grooves, and the one sidewall, the back-part side supply hole being configured to supply the chemical liquid to the gap between the substrate, which is engaged with the holding groove located closest to the back part, and the one sidewall. 
 
     
     
       11. A substrate processing apparatus comprising:
 a process tank including a pair of opposed sidewalls, the process tank being configured to store a chemical liquid therein and to process a plurality of substrates by the chemical liquid; 
 a substrate holding mechanism including a holding part configured to hold the plurality of substrates vertically, and a back part connected to the holding part, the back part being interposed between the substrates held by the holding part and one sidewall of the pair of opposed sidewalls of the process tank when the substrate holding mechanism is loaded into the process tank, the substrate holding mechanism being configured to immerse the substrates held by the holding part into the chemical liquid; and 
 a heating device disposed on the process tank, the heating device being configured to heat the stored chemical liquid; 
 wherein 
 the heating device includes a first heating device disposed on the one sidewall of the process tank, and a second heating device disposed on the other sidewall thereof, 
 a control unit is connected to the first heating device and the second heating device, 
 wherein the control unit is configured to independently control an energy output of the first heating device and an energy output of the second heating device by varying values of currents provided to the first heating device and the second heating device such that the energy output of the first heating device is smaller than the energy output of the second heating device, so as to heat the chemical liquid stored in the process tank, and 
 when the substrate holding mechanism is loaded into the process tank, the back part is interposed between the substrates held by the holding part and the first heating device. 
 
     
     
       12. The substrate processing apparatus according to  claim 11 , wherein the control unit controls the first heating device and the second heating device such that the energy output of the first heating device relative to the energy output of the second heating device is 30% to 50%.